# Sparsity Detection in Jacobian

**URL:** <https://discourse.julialang.org/t/sparsity-detection-in-jacobian/75756>\
**Category:** Performance\
**Tags:** question, diffeq, sparse, symbolics\
**Created:** [February 3, 2022, 8:48pm UTC](https://discourse.julialang.org/t/sparsity-detection-in-jacobian/75756 "2022-02-03T20:48:06Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ziolai](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ziolai/32/23422_2.png) [@ziolai](https://discourse.julialang.org/u/ziolai)\
**Post date:** [February 3, 2022, 8:48pm UTC](https://discourse.julialang.org/t/sparsity-detection-in-jacobian/75756/1 "2022-02-03T20:48:06Z")

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When trying to run

[https://diffeq.sciml.ai/stable/tutorials/advanced\_ode\_example/#Declaring-a-Sparse-Jacobian-with-Automatic-Sparsity-Detection](https://diffeq.sciml.ai/stable/tutorials/advanced_ode_example/#Declaring-a-Sparse-Jacobian-with-Automatic-Sparsity-Detection)

I obtain

MethodError: no method matching jacobian\_sparsity(::var"#7#8", ::Array{Float64, 3}, ::Array{Float64, 3})  
Closest candidates are:  
jacobian\_sparsity(::Any, ::Any) at /Users/djplahaye/.julia/packages/Symbolics/sITWZ/src/diff.jl:358

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<div class="post-metadata">

**Author:** ![ziolai](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/ziolai/32/23422_2.png) [@ziolai](https://discourse.julialang.org/u/ziolai)\
**Post date:** [February 4, 2022, 4:53pm UTC](https://discourse.julialang.org/t/sparsity-detection-in-jacobian/75756/2 "2022-02-04T16:53:11Z")

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Managed to by-pass this issue by reverting to the older SparsityDetection functionality. Insight into how to do the same using Symbolic remains valuable to receive. Thx!